A common filtering procedure is to form a filter wheel or disc made up of individual sectors which is designed to be passed in a rotational manner through a container of material to be filtered. A filter material in the form of a bag is mounted on the sectors and a source of suction is provided to draw the filtrate through the filter bag leaving a cake of residue on the bag surface. At a predetermined time and location, fluid is forced into the interior of the bag to drive the cake from the exterior of the filter bag.
The various types of available filters of this nature are designed to provide a quick and efficient means for removing the filtrate as it is drawn through the filter material. One way of accomplishing this is to provide a series of grooves and the surface of the supporting structure or sectors which direct the filtrate to a drainage opening where it is removed. A recent example of a system of this type is present in U.S. Pat. No. 3,917,534.
Other patents which further define the general state of the background art in regard to filtering systems and particularly disc-like filtering systems appear in U.S. Pat. Nos. 2,601,633; 2,902,164; 3,398,833; and 3,536,195.
While the state of the art is highly developed, there is still room for improvement of flow characteristics during removal of the filtrate so that a more efficient and streamline flow with low turbulence can be obtained. It is also of importance, in addition to improving the flow characteristics of removal of the filtrate and eliminating the occurrence and amount of back-flow, that the disc sectors be formed of low cost material and in an inexpensive and efficient manner to facilitate assembly and mounting and removal of filter bags when the disc is being used in the filtering operation.